[数学讨论稿3] 已阅而是就输血讨论稿201-300（更新至300，2.16 -22:15)

jesstheone

i got A too... but not sure if is right..

jesstheone

Can Someone show me how to do Q288?

jesstheone

Thanx thanx

jesstheone

i got A..not sure if is right

Round887

顶顶顶！

zhoupeng315

我想问下295题 为什么得出来是Monday？我怎么算都算不到是Monday。是不是答案错了？还是我做错了 求高人提点

jesstheone

291.【Brooke112】PS。。。 Half of the number K is decreased by 10%k, and then the result is divided by 4. The final result is 180. What is k?

这个题他是不是说k的一半又降了10%之后除以4等于8啊
如果这样的话就是50%K（1-10%K）=180*4 就是45%k=720 就是1600.......不知道对不对

-- by 会员 gkdlymssq (2012/2/15 22:18:46)

but if you use 1600*0.5*0.9/4=180.. but if you use 1800*0.5*0.9/4=202.5... so i think is 1600... not sure if i am right lol...

觉得是(0.5K-0.1K)/4 = 180  所以 K=1800.
如果是decreased by 10%, 就是0.5K*(1-0.1), 但是decreased by 10%K, decreased的是个 数目, 所以应该是直接减去0.1K

-- by 会员 jingqh (2012/2/16 4:21:32)

我也觉得应该是1800

-- by 会员 CiciSissi (2012/2/16 11:50:01)

jesstheone

291.【Brooke112】PS。。。 Half of the number K is decreased by 10%k, and then the result is divided by 4. The final result is 180. What is k?

这个题他是不是说k的一半又降了10%之后除以4等于8啊
如果这样的话就是50%K（1-10%K）=180*4 就是45%k=720 就是1600.......不知道对不对

-- by 会员 gkdlymssq (2012/2/15 22:18:46)

but if you use (1600*0.5*0.9)/4=180.. but if you use (1800*0.5*0.9)/4=202.5... so i think is 1600... not sure if i am right lol...

觉得是(0.5K-0.1K)/4 = 180  所以 K=1800.
如果是decreased by 10%, 就是0.5K*(1-0.1), 但是decreased by 10%K, decreased的是个 数目, 所以应该是直接减去0.1K

-- by 会员 jingqh (2012/2/16 4:21:32)

我也觉得应该是1800

-- by 会员 CiciSissi (2012/2/16 11:50:01)

-- by 会员 jesstheone (2012/2/16 13:12:50)

jesstheone

Nevermind.. misread the question.. it should be 1800... sorry...

291.【Brooke112】PS。。。 Half of the number K is decreased by 10%k, and then the result is divided by 4. The final result is 180. What is k?

这个题他是不是说k的一半又降了10%之后除以4等于8啊
如果这样的话就是50%K（1-10%K）=180*4 就是45%k=720 就是1600.......不知道对不对

-- by 会员 gkdlymssq (2012/2/15 22:18:46)

but if you use (1600*0.5*0.9)/4=180.. but if you use (1800*0.5*0.9)/4=202.5... so i think is 1600... not sure if i am right lol...

觉得是(0.5K-0.1K)/4 = 180  所以 K=1800.
如果是decreased by 10%, 就是0.5K*(1-0.1), 但是decreased by 10%K, decreased的是个 数目, 所以应该是直接减去0.1K

-- by 会员 jingqh (2012/2/16 4:21:32)

我也觉得应该是1800

-- by 会员 CiciSissi (2012/2/16 11:50:01)

-- by 会员 jesstheone (2012/2/16 13:12:50)

-- by 会员 jesstheone (2012/2/16 13:14:02)

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Sunnyxu0819

LZ，觉得240选C ，因为单从条件一看，y可以等于1，然后x为5000的1/3次方，只有和2结合才可以得出y=5